Improvement in sewing-machines



Patented April 19, 1864.

R. THOMPSON.

SewinglViachine.

llNrrnn rares Fierce.

ArnNr ROSEWELL THOMPSON, OF BOSTON, ASSIGNOR. TO ALFRED B.' ELY, OF

NEWTON, MASSACHUSETTS. l

IMPROVEMENT IN SEWING-MACHINES.

Specification forming partof Letters Patent N0. QQAQQ, dated April 179, 1864.

To all lwhom it may concern Be it known that I, RosEwELL THOMPSON, of Boston, in the county of Suffolk and Gommonwealth of Massachusetts, have invented a new and useful Improvement in Double- Spool Shuttle-Stitch Sewing-Machines; and l do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the accompanying drawings, forming a part of this specification, in which- Figure l is a side elevation of those parts of themachine to which my improvement relates; Fig. 2, a front elevationof the same; Fig. 3, a side view of the lower spool-case removed; Fig. 4, a bottom view of the same and its holder Q.

The drawings are full size, and like parts are indicated by the sameletters in all.

The nature ot' my invention consists, first, r

in making the shuttle-stitch by means of a double revolving hook so constructed as to close together when entering the loop formed by the needle, and spread the thread or loop apart suflicientlywide during its revolution to yencompass and permit the use of a commercial spool, thereby avoiding the necessity of rewinding the thread second, in so constructing the spool-case as to rest entirely on the center of its lower end, in order to facilitate the passage ofthe thread under and around the same; third, in the employment of a hinged wire, T, constructed and arranged as hereinafter described, for the purpose of supporting the spool-case, allowing it to rest upon its center, and be readily removed or inserted; and, fourth,in the use ofthe shield W,combined and arranged as hereinafter described, for the purpose of protectin g the cast-off 7 thread from the revolving hooks, and causing the under thread to draw perpendicularly from the center of the spool-case, and thereby prevent the latterfrom bearing hard against its holder'.

To enable others skilled in the art to make and use my improvement, l will now proceed to describe its construction and operation.

` A is the table.

B and B are studs attached to the under side of the table, through the lower ends ot' which the shaft E passes and turns in suitable bearings.

C is the driving-pulley, fast to the shaft E.

D is the pitman, which vibrates the armthat carries the needleZ.

F is a crank attached to the end of shaftE.

G is a stud made fast to the table.

H is a vertical shaft, the upper end of which (as represented by the dotted lines in Fig l) turns in the stud G, being prevented from dropping out by means of the screw p.

l is the hook-lever, which is provided with a slot to receive the shaft H and turns on the fulcrum J. On the short end of leverl is a ball, l', which plays freely in the round hole F in the crank F.

K is one part of the double hook, the shape and size of which are shown in Figs. 1 and 2, Z being a notch for retaining the upper thread until it is carried under the lower spool.

L and L are starts on the under side ofthe lever I. 1

0 is a steel wire, shaped as shown in Figs. l and 2, and constituting the other part of the double hook, being provided with a notch, on,

for retaining the upper thread until it is carried under the lower spool.

As represented in Fig. l, this wire O slides through holes in the starts L and L.

M is a sliding block, through the upper part of which is a hole to receive the wire O, to which it is confined by means of a set-screw,n.

N is a strip of sheet-iron or steel, one end of which is pivoted to the bottom of the block M and the opposite end to the bottom of the shaft H.

Thus combined and arranged it is obvious that the pointed end of the wire O will be at the greatest distance from the hook K when the crank F is in the position represented in Fig. l, and that the two hooks will gradually approach each other as the crank F descends toward its lowest point of motion, and before they reach the loop formed by the needle the two hookpoints will be together, so as to ena ter said loop precisely as they would if consti tuting a single hook, and then as the crankF rises and the hooks descend the latter will be gin to separate, spreading the loop of the up per thread (which is retained by the notches land m) until it is distended far enough to pass around the spool-case R.

P is a stud attached to the bottom of the table A, as represented in Figs. 1 and 2.

Q is a piece of sheet-brass or other suitable metal, one edge of which is riveted to the stud P, as shown in Figs. 1, 2, and 4, the opposite edge, Q', being bent outward, as represented in Fig. 4. The main body of this holder Q, as shown in Fig. 4, is cylindrical--about threefourths of a cylinder-large enough to receive the removable spool-case R, and also give sufficient space for the expanded loop formed by the needle to be freely passed between them.

R is the removable spool-case, of sheet-brass or other suitable metal, open at the top and provided with a bottom, as shown in Figs. 2, 3, and 4.

S is a strip of sheet metal, bent and attached to the spool-case R, as represented in Fig. 3, and forming in effect a continuation of the case. i f T is a wire bent as shown in Figs. Zand 1, the upper end e'ntering the square block U, to which it is confined by means of the set-screw o, the object of said wirebeing to support the spool-case, and at the same time allow the thread to pass freely between it andthestrip S.

V is a straight spring, resting on the top ot' the block U, by means of which the wire T is held either in the position, shown in Fig. 2 or at an angle of forty-tive degrees with the same, when said wire is thrown back so that the spool-case may be inserted or removed.

X is a wire bent as seenin Figs. 3 and 4, and passing diagonally over the spool case, (sce Fig. 1,) to which it is attached at both eX- 'tre1nities, the purpose of said wire being,tirst,

.to prevent the case R from turning in the holder Q, (See Figs. 1 and 4,) and, second, to assist in throwing the loop to the front side of the case.

W is an arch of sheet metal, bent as shown l in Figs. 1 and 2, one end being riveted to the vent the spool-case from being forced against the side of the holder.

a is the tension -wire ot' the Linder thread, which passes through the thumbpiece c, to

-which it is confined by means of the set-screw d and up through a tube, r, the latter, r, being provided with a spiral spring, by means of which sufficient friction is given to the wire a to keep it in place wherever it is turned. Through the top of a is a hole, b. Thus to the lower spool thread passing from vspool g through the holes c, f, and b any required degree of tension can be given by simply turningV the wire a., so as to wind the thread more or less around it.

- Y is the feed-bar, pivoted near its center to the under side of the table, motion being communicated to it by means of the arm 7L and cams on shaft E in the usual manner.

j isa set-screw, by means of which the length of the stitch may be varied.

Havin g thus described the construction and operation of my improvement, whatI claim as my invention, and desire to secure by Letters Patent, is-

1. Making the shuttle-stitch by means of a double revolving hook, so constructed as to close together when entering the loop formed by the needle, and spread the thread or loop apart wide enough during its revolution to encompass a commercial spool, substantially as described.

2. The spool-case R, so constructed that its lower end may rest upon its-center only to facilitate the passage of the thread under and around the same, substantially as described.

3. The hinged wire T, in combination with the spool-case R, constructed and operating substantially as described.

4. The shield W, combined and arranged Asubstantially as set forth, for the double pur- Rosnwnm. 'rHoMP-soN.

Witnesses:

N. AMES, N. EVANS, Jr. 

